What is the production method of lithium iron phosphate battery cathode material

Lithium iron phosphate battery cathode material processing method 1. Carbothermal reduction method Carbothermal reduction method is also a kind of high temperature solid phase method, which is relatively easy to industrialize synthesis method, most of which use lithium dihydrogen phosphate (LiHPO4) and iron trioxide. (Fe2O3) or ferroferric oxide and sucrose as raw materials. After being evenly mixed, it is roasted under the protection of high temperature soft fish gas or nitrogen. Carbon reduces ferric iron to divalent iron, which is to synthesize lithium iron phosphate by carbothermal reduction method. . Advantages: The oxidation reaction that may be triggered during the mixing of raw materials is processed, making the synthesis process more reasonable, and improving the conductivity of the material. Disadvantages: The reaction time is relatively long, the temperature is difficult to control, and the control conditions for product consistency are more stringent, and it is difficult to adapt to industrial processing. 2. Hydrothermal synthesis method Hydrothermal synthesis method belongs to the field of wet method. It uses soluble ferrous salt, lithium salt and phosphoric acid as raw materials to directly synthesize LiFePO4 under hydrothermal conditions. Because the solubility of oxygen in the hydrothermal system is very small , The synthesis of LiFePOA in the hydrothermal system provides an excellent inert environment. Advantages: The hydrothermal method can prepare ultra-fine particles in the liquid phase, and the raw materials can be mixed at the molecular level. It has the advantages of average phase, small powder particle size and easy operation, and has the advantages of easy mass production, good product batch stability, and low cost and easy availability of raw materials. At the same time, do not inert atmosphere during processing. Disadvantages: The structure of the product prepared by the water-cooking synthesis method often has iron dislocation, which generates metastable FePO, which affects the chemical and electrochemical properties of the product. At the same time, there are also shortcomings such as uneven particle size, impure phases, large equipment investment (high temperature and high pressure reactor design and manufacture are difficult, and the cost is high) or the process is more complicated. 3. In addition, sol-gel synthesis method, liquid phase co-precipitation method, microwave synthesis method, etc. are also used in the preparation of LFP raw materials. These processes have their own advantages and disadvantages, but after the improved process, the first three are more widely used. A123 in the United States and Phostech in Canada use the solid phase method, Valence in the United States uses the carbothermic reduction method, and LG Chem. Use the continuous hydrothermal synthesis method. In the material preparation process, conductive carbon coating is a key technology in the LiFePO2 preparation process. By pre-coating a high-quality conductive carbon layer on the surface of the foil, A123 effectively reduces the internal resistance of the battery and improves the high-rate discharge capacity of the lithium iron phosphate battery. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: What are the performances of the long life of lithium iron phosphate battery?